const { reject } = require("lodash");

/*
  将下面异步代码使用 Promise 的方法改进
  尽量用看上去像同步代码的方式
  setTimeout(function () {
    var a = 'hello'
    setTimeout(function () {
      var b = 'lagou'
      setTimeout(function () {
        var c = 'I ♥ U'
        console.log(a + b +c)
      }, 10)
    }, 10)
  }, 10)
*/
new Promise(function (resolve, reject) {
  setTimeout(() => {
    var a = 'hello';
    resolve(a);
  }, 10);
}).then(
  (a) => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        var b = 'lagou';
        resolve(a + b);
      }, 10);
    })
  }

).then(
  (value) => {
    setTimeout(() => {
      var c = 'I ♥ U';
      console.log(value + c);
    }, 10);
  }
);

